Area Forecast Discussion
Issued by NWS Buffalo, NY
Issued by NWS Buffalo, NY
752 FXUS61 KBUF 141721 AFDBUF Area Forecast Discussion National Weather Service Buffalo NY 121 PM EDT Mon Sep 14 2026 .WHAT HAS CHANGED... Minor changes to the forecast with this update. && .KEY MESSAGES... 1) Dry weather continues through Tuesday with cool temperatures giving way to a warming trend by Tuesday afternoon. 2) Several rounds of showers and isolated thunderstorms Tuesday night through Thursday as a frontal boundary stalls nearby. && .DISCUSSION... KEY MESSAGE 1...Dry weather continues through Tuesday with cool temperatures giving way to a warming trend by Tuesday afternoon. Surface high pressure will briefly build over the eastern Great Lakes and New England tonight. Diurnal cumulus will dissipate this evening with the loss of daytime heating, setting up a good radiational cooling night with mainly clear skies and light winds. Lows will drop back into the 40s areawide with the exception of the immediate lakeshores. Some of the normally colder Southern Tier valleys and Tug Hill region may make a run at the upper 30s. Lows in Lewis County will likely stay just mild enough to prevent any patchy frost, with a better frost potential found farther east across portions of the Adirondacks. The high will drift off the New England coast Tuesday, with strong warm advection developing in its wake. This will boost highs well into the 70s in most areas after a cool start to the day. Strong warm advection and moisture transport aloft will bring a northwest to southeast increase in high clouds, but dry weather will continue to prevail through early evening. KEY MESSAGE 2...Several rounds of showers and isolated thunderstorms Tuesday night through Thursday as a frontal boundary stalls nearby. The pattern will turn unsettled again Tuesday night through Thursday as a frontal zone oscillates north and south across the Ohio Valley and eastern Great Lakes. The most widespread rain will likely be Wednesday night through Thursday when forcing and moisture transport maximizes. Tuesday night through Wednesday, a weak cold front will move southeast across the eastern Great Lakes. Most of the large scale forcing for ascent will pass well north of the area across Quebec, leaving minimal height falls along the weak frontal zone in the eastern Great Lakes. Weak low level moisture convergence may support a few scattered showers and possibly an isolated thunderstorm, along with plenty of rain free time as well. The frontal zone may briefly sag south of the area into Ohio and PA late Wednesday, then move back north as a weak wave of low pressure develops and runs east down the boundary. The frontal wave and tightening thermal packing along the boundary will bring a period of stronger frontogenesis, moisture convergence, and deformation late Wednesday night through Thursday, with rain becoming more widespread. Enough instability may develop for a few embedded thunderstorms as well. The orientation of the frontal zone laying out in an east-west fashion parallel to the mid/upper level flow combined with PWAT values reaching or exceeding 1.75" suggests some potential for locally heavy rainfall. A mid/upper level trough is forecast to sharpen across Quebec Thursday night, forcing the frontal zone southward with rain ending from north to south. High pressure will then build just north of the Great Lakes Friday through Saturday, bringing a return to dry weather. && .AVIATION /18Z MONDAY THROUGH SATURDAY/... Diurnal cumulus will continue through late afternoon with mainly VFR bases. High pressure will settle overhead tonight, with mainly clear skies and VFR in most locations. Expect patchy river valley fog with local IFR overnight across the Southern Tier and Lewis County. Fog is unlikely to impact KJHW. Tuesday, high pressure will drift off the New England coast. High clouds will gradually increase from west to east ahead of the next trough, with VFR prevailing. Outlook... Tuesday night through Wednesday...VFR/MVFR with scattered showers possible. Slight chance of a thunderstorm. Wednesday night through Thursday...MVFR/IFR with showers likely at times along with a chance of a few thunderstorms. Friday...MVFR CIGS early, improving to VFR. Saturday...VFR. && .MARINE... High pressure will build over the lower Great Lakes and New England tonight, with a brief period of light winds. The high will drift off the New England coast Tuesday, with increasing southerly winds producing choppy conditions on both lakes, especially in offshore waters. Winds and waves may approach Small Craft Advisory criteria offshore of Jefferson County for a time later Tuesday afternoon through Tuesday evening. Winds and waves will gradually subside Wednesday as a weak front moves southeast across the lower Great Lakes and the pressure gradient weakens. && .BUF WATCHES/WARNINGS/ADVISORIES... NY...None. MARINE...None. && $$ DISCUSSION...Hitchcock AVIATION...Hitchcock MARINE...Hitchcock